Unless otherwise indicated herein, the description provided in this section is not itself prior art to the claims is not admitted to be prior art by inclusion in this section.
In a wireless communication system, a base station provides one or more coverage areas, such as cells or sectors, in which the base station may serve wireless communication devices (WCDs), such as cell phones, wirelessly-equipped personal computers or tablets, tracking devices, embedded wireless communication modules, or other devices equipped with wireless communication functionality. Further, the base station may be in communication with network infrastructure including a gateway system that provides connectivity with a transport network such as the Internet for instance. With this arrangement, a WCD within coverage of the base station may engage in air interface communication with the base station and may thereby communicate via the base station and gateway system with various other entities.
In general, a base station may provide service in accordance with a particular air interface protocol or radio access technology, examples of which include Orthogonal Frequency Division Multiple Access (OFDMA (e.g., Long Term Evolution (LTE) or Wireless Interoperability for Microwave Access (WiMAX)), Code Division Multiple Access (CDMA) (e.g., 1×RTT and 1×EV-DO), and Global System for Mobile Communications (GSM), IEEE 802.11 (WiFi), and others now known or later developed.
In accordance with the air interface protocol, each coverage area provided by the base station may operate on one or more radio frequency carriers, each defining one or more ranges of frequency spectrum and having a respective downlink channel for carrying communications from the base station to WCDs and a respective uplink channel for carrying communications from the WCDs to the base station. Such carriers may be frequency division duplex (FDD), in which the downlink and uplink channels are defined as separate respective ranges of frequency, or time division duplex (TDD), in which the downlink and uplink channels are defined on a common range of frequency but distinguished through time division multiplexing. Further, the downlink and uplink channels may then define various sub-channels for carrying particular communications, such a control signaling and data (e.g., user communications or other application layer data) between the base station and served WCDs.
As WCDs enter into coverage of the base station, the base station may become configured with connections to serve those WCDs. For instance, for each such WCD entering coverage on a particular carrier, the base station may engage in signaling with the network infrastructure to establish a bearer connection for carrying data between the gateway system and the base station, and the base station may work with the WCD to establish a radio-link-layer connection for carrying data over the air between the base station and the WCD on the carrier.
Once so configured, the base station may then serve the WCDs. For instance, when data arrives over the transport network for transmission to a WCD, the gateway system may transmit the data over the WCD's bearer connection to the base station, and the base station may then transmit the data over the WCD's radio-link-layer connection to the WCD.